Pyrrolidinylthio carbapenem derivatives with a broad antibacterial spectrum (the below compound II) are known as useful antibiotics (see, Patent Document 1). The compound (I) of the present invention is a synthetic intermediate and described in Patent Document 1, but has not been isolated as a specific crystal form. Especially in an industrial manufacturing method, preferred is that a compound produced in each process has high purity or is isolated and purified as a crystal form which is easy to handle. However, a crystal of the compound (I) has not been isolated. Additionally, a method for producing the compound (II) with high purity by deprotecting a crystal of the compound (I) with high quality has not been reported. A crystal of the compound (II) and a method for producing thereof is known (see, Patent Document 2).
(Patent Document 1) Japanese Patent Publication (Kokai) 1993-294970
(Patent Document 2) International Publication WO 95/29913